Electricity is commercially generated using rotating generating equipment. The power of rotation may be supplied in a variety of ways, a common method being the use of combustible fuel, usually gas or oil in a gas turbine generator. Another frequently employed means is a hydraulic turbine generator utilizing the energy of the head of an elevated supply of water.
One problem encountered by the electrical generation and distribution industry is that of meeting peak load demands. For this purpose a number of pump-back facilities have been established. These facilities store energy in the form of water head, utilizing energy during the periods when it is most readily and economically available and when surplus generating capacity exists, and recovering the energy to meet peak load demands. Typically, these pumpback facilities use electrical power to drive a generator which, when energized, functions as an electric motor, to power the turbines which, when driven, function as a pump, to move water from a lower elevation through a penstock to an upper elevation, usually an elevated lake. When the flow of water is reversed, the turbine drives the generator to recover the energy. While the recovered energy is always less than the amount of energy required to move the water to the upper elevation, nevertheless the advantage of having the stored energy available to meet peak loads is economically justified compared to the cost of building and maintaining additional generating facilities to meet peak load demands.
Most generating facilities in the United States at the present time utilize some sort of combustible fuel, and frequently employed means for generating electricity utilizes a gas turbine as a prime power source. Gas turbines utilize a gas fuel input, usually natural gas, but can be devised to employ gas obtained by coal gassification or liquid fuel in vapor form. To achieve maximum efficiency in the gas turbine, air must be supplied under pressure to mix with the fuel to achieve the combustion necessary to produce the required energy output. One problem with the use of gas turbines is that of generating the compressed air. A substantial amount of the energy which otherwise would be available from a gas turbine generator is used in compression of air employed in the gas turbine itself.
The present invention is directed towards the use of an alternate means of providing the compressed air required by a gas turbine generator and particularly concerns the combination of the gas turbine generator and a water turbine generator with a hydraulic air compressor as a means of compressing air for use in the gas turbine generator. Hydraulic air compressors are well known, therefore, the present invention is not directed to the concept of a hydraulic compressor per se but to a unique combination of hydraulic and gas turbine generation of electricity utilizing hydraulic head energy to provide compressed air for the gas turbine so that the combination of hydraulic and gas turbine generated electricity may be manufactured according to optomized factors of energy demand, fuel costs, and water availability.
It is therefore an object of this invention to provide a system for generating electrical energy utilizing combined water power and combustible fuel.
This object as well as other and more specific objects of the invention will be fulfilled in the following description and claims, taken in conjunction with the attached drawings.